Oaths Empowering Mitzvah Fulfillment

וידבר משה אל ראשי המטות כו' במדרש ונשבעת חי ה' באמת כו' אם יש בך מדות הללו כו'

"And Moshe spoke to the heads of the tribes" (Bamidbar 30:2), and so on. In the Midrash: "'And you shall swear, as Hashem lives, in truth' (Yirmiyahu 4:2)" — if these traits are found within you, and so on.

The Sfas Emes opens with the pasuk about Moshe addressing the heads of the tribes regarding vows, and cites a Midrash that swearing by Hashem's Name in truth is permitted only to one who possesses certain elevated traits.

פי' לכך נאמר ראשי המטות שרק לצדיקים מותר השבועה

The explanation is this: it is therefore said "the heads of the tribes," for only to the tzaddikim is the oath permitted.

He explains that the Torah specifically addresses "the heads of the tribes" because the oath, used properly, is the domain of tzaddikim alone.

כי הנה באמת עיקר מצות נדר ושבועה הוא עפ"י מאמרם ז"ל מנין שנשבעין לקיים המצות שנא' נשבעתי ואקיימה כו'

For behold, in truth the essence of the mitzvah of a vow and an oath is in accordance with the words of our Sages, of blessed memory: from where do we know that one may take an oath to fulfill the mitzvos? As it is said, "I have sworn, and I will fulfill it" (Tehillim 119:106), and so on.

He brings the teaching of Chazal that a person may take an oath in order to bind himself to fulfilling the mitzvos, learned from Dovid HaMelech's words "I have sworn, and I will fulfill it."

פי' שע"י השבועה והנדר שאדם מקבל עליו לעשות המצוה קבלה זו נותנת לו כח לגמור המעשה כמו כל מצוה שהיא כח וסיוע מהבורא ית'

The explanation is that through the oath and the vow that a person takes upon himself to perform the mitzvah, this acceptance grants him strength to complete the deed — just as every mitzvah carries strength and assistance from the Creator, may He be blessed.

The deeper point is that when a person swears or vows to do a mitzvah, that very acceptance draws down strength to carry the deed to completion — paralleling how every mitzvah itself brings divine assistance from the Creator.

אשר קדשנו במצותיו וצונו

"Who sanctified us with His mitzvos and commanded us."

He cites the words of the berachah, "Who sanctified us with His mitzvos and commanded us," as the source of that empowering force that comes through being commanded.

כמו כן ע"י השבועה נאמר ככל היוצא מפיו יעשה וזה כחן של ישראל בפה ולכן אנו מקבלין עלינו עול מלכות שמים בכל יום

So too, through the oath it is said, "according to all that issues from his mouth he shall do" (Bamidbar 30:3) — and this is the strength of Bnei Yisrael, which lies in speech. And therefore we accept upon ourselves the yoke of the Kingdom of Heaven each and every day.

Just as a mitzvah empowers, so too the oath obligates a person to make real whatever leaves his mouth; this power of speech is the unique strength of Bnei Yisrael, which is why we accept the yoke of Heaven daily.

וגם שבע ביום הללתיך ז' ברכות דק"ש הוא באמת שבועה שאדם מקבל עליו בכל יום לקיים מצות הבורא ית' ומחדש השבועה שמושבעין ועומדין עליו מהר סיני וקבלה זו בכחה להטות כל נפש האדם להבורא ית'

And also, "Seven times a day I praise You" (Tehillim 119:164) — the seven berachos of Krias Shema are in truth an oath that a person takes upon himself each day to fulfill the mitzvos of the Creator, may He be blessed, and he renews the oath by which we are sworn and bound since Har Sinai; and this acceptance has within it the power to incline a person's entire soul toward the Creator, may He be blessed.

The seven daily praises hinted at in Tehillim correspond to the seven berachos of Krias Shema, which function as a renewed daily oath reaffirming the binding commitment accepted at Har Sinai, with the power to turn one's whole soul toward Hashem.

ומכש"כ ראשי בני ישראל שעל ידי דיבורם וקבלת מלכות שמים שהם מקבלים עושים רושם והטי' לכלל לבות בנ"י לכן נקראו ראשי המטות

And how much more so the heads of Bnei Yisrael, for through their speech and the acceptance of the Kingdom of Heaven that they receive, they make an impression and an inclination upon the hearts of all Bnei Yisrael — therefore they are called "the heads of the tribes."

All the more so the leaders of Bnei Yisrael, whose speech and acceptance of the Kingdom of Heaven leave an impression on the hearts of the entire nation — which is precisely why they are titled "the heads of the tribes."

וכ' זה הדבר כו' שנמסר בידם כח הדיבור שחל על דבריהם שם שמים ביותר כנ"ל:

And it is written, "This is the thing" (Bamidbar 30:2), and so on — that the power of speech was handed over to them, for upon their words the Name of Heaven rests with even greater force, as explained above.

He concludes that the phrase "This is the thing" signals that the power of speech was entrusted to these leaders, so that the Name of Heaven rests upon their words with special intensity.

Summary: The Sfas Emes asks why the parsha of vows is addressed specifically to the heads of the tribes, and answers that the oath, properly understood, belongs to tzaddikim. The true essence of a vow or oath is to bind oneself to fulfilling the mitzvos, and this very acceptance draws down strength from the Creator to complete the deed, just as the words "Who sanctified us with His mitzvos" reflect the empowering force of being commanded. The unique strength of Bnei Yisrael lies in speech, which is why we accept the yoke of the Kingdom of Heaven each day; the seven berachos of Krias Shema serve as a daily renewal of the oath we have stood bound to since Har Sinai, with the power to incline the entire soul toward Hashem. All the more so the leaders of Bnei Yisrael, whose acceptance of Malchus Shamayim leaves an impression upon the hearts of the whole nation — and therefore they are called "the heads of the tribes," since the Name of Heaven rests upon their words with special force.